It may seem that way after Satur day’s horrific crane collapse on E. 51st Street, which killed seven – six of them construction workers – and injured 24, eight seriously (the accident also caused massive traffic and transit disruptions).

The Manhattan DA’s office (which still has not completed its probe of the Deutsche Bank building fire that occurred seven months ago today) and the city Department of Investigation will attempt to determine blame. That’s as it should be – indeed, must be.

But some realism also is called for.

Saturday’s disaster was highly unusual. As Mayor Bloomberg noted, there are 250 such cranes operating in the city on any given day; last year, the new crane and derrick permits totaled 917; some 188 more have been issued this year.

Yet there were only eight crane-related accidents last year.

The fact remains, as the mayor added, that “construction is a dangerous thing.”

That’s especially true of high-rise construction, like the 43-story building that was going up on Second Avenue – the sort of structure that can only be built with the use of large cranes.

The anti-development crowd will use the tragedy to press for a moratorium on the city’s current building boom. But that would be a mistake: Development is what keeps New York vital; indeed, it is a key reason why the city has managed to rebound since 9/11.

Since 2002, the number of permits for new construction or major renovation work has leaped by 23.3 percent, to 86,915 last year. And that trend must continue.

Opponents point to the increase over that period in crane complaints. But many, in fact, turn out to be unjustified.

Yes, the construction site on E. 51st Street had been issued 13 violations, some of which were still unresolved last weekend. But as Bloomberg said, “every large construction site has violations” – and these mostly involved items the city feared might blow off the building.

None involved the crane itself, which was inspected just a day before the collapse and was found to be in full compliance with safety guidelines.

It may be that city needs to adjust either its safety rules or enforcement practices. Thus the probe must be thorough and comprehensive – but swift.